Lung cancer is the leading cause of cancer-related deaths worldwide. Based on status quo detection strategies and therapies, only 16% of patients diagnosed last year with lung cancer will survive for five years. Lung cancer is the result of a wide range of genetic changes, many of which indirectly affect protein kinase signaling pathways that disrupt the normal homeostasis of cell proliferation and apoptosis. Protein kinases are now an important class of targets for lung cancer therapy. The purpose of the experiments proposed here is to develop and validate quantitative methods in phosphoproteomics capable of probing differences in cellular signaling in lung tumors that correlate with patient outcomes. To do this, we will i) develop a quantitative phosphoproteomics technology for clinical lung cancer specimens, ii) develop phospho-multiple reaction monitoring (p-MRM) methods that target substrates of clinically relevant kinases, and iii) deploy these methods to study differences in cellular signaling in tumors from a limited cohort of non-small cell lung cancer patients. We anticipate that the successful conduct of the experiments proposed here will provide translational scientists and thoracic oncologists with an entirely new dimension of biomedical information which will enable the discovery of new treatment strategies, improve assessments of patient responsiveness to kinase inhibitor therapies at the molecular level, and allow for highly individualized decisions regarding patient care.